This invention relates generally to a mounting strategy for batteries, and more particularly to using such a strategy for various battery modular configurations where the batteries are used to generate motive power for vehicular and related transportation applications.
Various batteries, including lithium-ion, lead acid and nickel-metal hydride variants, may be configured to supplement or supplant conventional internal combustion engines (ICEs) for automotive and related transportation applications. The ability to passively store energy from stationary and portable sources, as well as from recaptured kinetic energy provided by the vehicle and its components, makes batteries (in general) and rechargeable batteries (in particular) ideal to serve as part of a propulsion system for cars, trucks, buses, motorcycles and related vehicular platforms. In one form suitable for automotive applications, the batteries are shaped as a generally thin rectangular cell with positive and negative voltage terminals emanating therefrom; several such batteries may typically be combined into larger assemblies—including modules that in turn can be formed into a complete system known as a battery pack—to generate the desired power output.
Current modules for holding, mounting or otherwise securing battery cells require numerous components, as well as complicated manufacturing processes to ensure such proper mounting. involving laser welding, spot welding, high part-count fasteners or the like. In the case of welding, such processes involve excessive temperatures, weld flash and related undesirable side effects. Furthermore, the use of compression limiters (along with their associated tie rods) along the stacking dimension of numerous battery cells into a larger battery module may produce tolerance problems during such stacking. Because the compression limiters tend to be made in large batches—where the dimensional consistency from one batch to another may be subject to fairly high tolerances—the stacking of such limiters (which individually may be acceptable) could, upon considering the multiplying effect of placing numerous such limiters into a module, produce unacceptable component size mismatches. Eccentricities in the bores formed in the compression limiters may exacerbate assembly problems, as the tie rods may be intolerant of a misaligned stack of apertures. Other components, such as compression bands (while helpful in ensuring proper dimensions of an assembled stack) and hold-down rails (helpful in providing discrete support of the assembled module onto a tray), introduce increases in overall part count, as well as reduce the overall modularity of the battery system. It is difficult to reconcile different vehicle platforms (where vehicular size, shape and power outputs or battery pack configurations dictate the final configuration of the battery pack) with production and inventory techniques such as those mentioned above, and an attempt to accommodate such a variety of configurations makes an approach based on the above inefficient and expensive.
It would be advantageous to have a modular mounting or attachment approach that accommodates number battery pack sizes and configurations.